Novel ternary molten salt electrolytes for intermediate-temperature sodium/nickel chloride batteries

Journal Article · Sat Dec 15 04:00:00 EST 2012 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2012.07.089· OSTI ID:1056757

Li, Guosheng; Lu, Xiaochuan; Coyle, Christopher A.; Kim, Jin Y.; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo

The sodium–nickel chloride (ZEBRA) battery is operated at relatively high temperature (250–350 °C) to achieve adequate electrochemical performance. Reducing the operating temperature in the range of 150200 °C can not only lead to enhanced cycle life by suppressing temperature-related degradations, but also allow the use of lower cost materials for construction. To achieve adequate electrochemical performance at lower operating temperatures, reduction in ohmic losses is required, including the reduced ohmic resistance of β"-alumina solid electrolyte (BASE) and the incorporation of low melting point secondary electrolytes. In present work, planar-type Na/NiCl₂ cells with a thin BASE (600 μm) and low melting point secondary electrolyte were evaluated at reduced temperatures. Molten salts used as secondary electrolytes were fabricated by the partial replacement of NaCl in the standard secondary electrolyte (NaAlCl₄) with other lower melting point alkali metal salts such as NaBr, LiCl, and LiBr. Electrochemical characterization of these ternary molten salts demonstrated improved ionic conductivity and sufficient electrochemical window at reduced temperatures. Furthermore, Na/NiCl₂ cells with 50 mol% NaBr-containing secondary electrolyte exhibited reduced polarizations at 175 °C compared to the cell with the standard NaAlCl₄ catholyte. Finally, the cells also exhibited stable cycling performance even at 150 °C.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1056757
• Report Number(s): PNNL-SA-85553; TE1400000
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Journal Issue: C Vol. 220; ISSN 0378-7753
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

reduced temperature
secondary electrolytes
sodium-nickel chloride battery